From 3ec159ab6be4dfcc51e339da562466eea38ce8b5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A9ter=20Szil=C3=A1gyi?= <peterke@gmail.com>
Date: Wed, 3 Jun 2015 15:43:12 +0300
Subject: [PATCH] eth/downloader: demote peers if they exceed the soft limits
 at 1 blocks already

---
 eth/downloader/peer.go | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/eth/downloader/peer.go b/eth/downloader/peer.go
index df54eecbd4..8ef017df71 100644
--- a/eth/downloader/peer.go
+++ b/eth/downloader/peer.go
@@ -93,11 +93,16 @@ func (p *peer) SetIdle() {
 		// Calculate the new download bandwidth allowance
 		prev := atomic.LoadInt32(&p.capacity)
 		next := int32(math.Max(1, math.Min(MaxBlockFetch, float64(prev)*scale)))
-		if scale < 1 {
-			glog.V(logger.Detail).Infof("%s: reducing block allowance from %d to %d", p.id, prev, next)
-		}
+
 		// Try to update the old value
 		if atomic.CompareAndSwapInt32(&p.capacity, prev, next) {
+			// If we're having problems at 1 capacity, try to find better peers
+			if next == 1 {
+				p.Demote()
+			}
+			if prev != next {
+				glog.V(logger.Detail).Infof("%s: changing block download capacity from %d to %d", p.id, prev, next)
+			}
 			break
 		}
 	}